The present invention relates to seals in turbines and turbo-machinery for sealing between stationary and rotary components and particularly relates to a combination of a brush seal and flexible beams for enhanced sealing capability
Current state-of-the art seals for turbines and turbo-machinery include brush seals and leaf seals. The construction of both are very complex and labor intensive, hence driving cost. For example, the individual bristles of brush seals are not modular. Rather, they are laid in by hand to form a bristle pack at a certain diameter. Specialized tooling is also required for brush seals of different diameters. This becomes a particular problem where brush seals are used in steam turbines which have a substantial number of stages e.g., 40-50 stages of different diameters and even additional and varying diameters depending upon seal location. Thus a very large number of differently sized seals would be required at substantial cost. Certain of these problems in brush seals have been addressed e.g. by offering brush seals in flexible strips in an effort to avoid tooling issues. However, such seals are often limited in their pressure drop capacity. Accordingly there is a need for seals between stationary and rotary components in turbines and turbo-machinery affording a modular seal construction with little or no dependency on diameter specific tooling, enhanced pressure capabilities and stiffness over conventional brush seals and the elimination of diameter specific tooling in most cases.